Casing for hydraulic shock absorbers



March 3, 1931. c. w. THOMPSON 1,794,307

- CASING FOR HYDRAULIC SHOCK ABSORBERS Original Filed Aug. 16, 1929 FIG. 1

a. '6 Z- i' 2' up la I5 |0 7\ 1' i i l 2 F j i l l H L H! l 5 INVENTOR CLARANCE. W. THOMPSON QwM vHQai I ATTORNEY S l atented Mar. 3, 193i UNITED su es PATENT oF ICE. f

CLARANCE w. rnoivrrsoiv, or wrrmmeromnnnnwami CASING r03 HYD AULIC sirocx ABSORBEBS Application filed August 16, iezasei'iai mazes-361. Renewed January 7, 1931.

My invention relates to that classof'shock absorbers described in my co-pendin'g application,-Serial No. 302,503," filed August 28, 1928, and has for its object to cheapen the 5 constructionof such devices.

- In that type of shock absorber, a plurality of ports, of varying length, is formedinthe side walls of the cylinder in which the oil is contained. "It is quite expensive to machine,

these ports, consequently I provide for the insertion of'a separate sleevefinside ofthe' cylinder, theports being milled'in this sleeve.

This, however, while; reducing theexpense of machining the ports, is an added expense for'material. a

' Attempts have been made: to form these ports by extruding them from the wall of the cylinder, but theexpense of this has I been prohibitive, owing to thefnecessity of i providing for a coll ap'sible' mandrel which I wouldextrudethe metal in the desired shape andlocation.

My invention has'for it's principal object, H

' Fig, 1 is a verticallongitudinal section through a shock'absorber inwhich the cylin- .der isformed in accordance with my invention;

' Fig. 2 is a cross-sectiom-taken on line 2-2 0 v Fig. 3 is a detail viewofthe upper inside skirtorbushing;

- Fig. 4; is a modified formyof-cylinder, and

Fig. 5 is a cross-section taken on line. 5-5

Similar reference numerals refer to -.simi-' lar parts throughout the entire description; As shown in the drawings, theshock ab sorber comprises a cylindrical casing; 1,

whichis provided with astufling-box 2 at its lower end, the casing'land 'stuflingmember 9, onthe continued 'mentof the piston 6. 1

box 2 i being formed integrally, if desired. In the stufiing-box 2 is mounted suitable packing 3, a gland 4, of standard construction, being providedto insure a tight joint between the packing 3 and a piston. Ifod 65. 5 which is .mounted and slidable. therein. This piston rod 5 carries a piston 6, thehead ofwhich is provided with a plurality offports 7. These ports 7 are closed, or partially closed, by means of a bottomvalve member -8, which mountedfbelow theheadiofthe piston. 6 and is slidable, up0nareduced' pony tion of the piston -rod 5. An intermediate valve member 9, ;mounted on the top of the head of the piston 6,-operates to Yclose, or partlally close, the ports 7 in the head of the piston 6. A top ,,valve member '10, mounted inthe upper part of the cylinder 1, contacts the'piston 6'onits upward movement,'and

operates to close such portions of said ports 7 as are not covered by the intermediate valve upward move- A pluralityfof wall ports 11 is formed in v the side walls or the'cylinder '1. These ports '11'areofvarying'length, so that thecontinuedmovementof the piston 6 in its'upward direction will obviously cut ofi? these ports 11 one by one. It willbeobviousgto persons skilled in the art, that asthese ports '11 are: greater in diameter than the piston 6, it would be impossible tostamp-:them'inthe wall of the cylinder 1'- and'withdraw the'punch or die through the reduced passage in which the'pist'on 6 wouldtravel'afterit'has passed '85 I v the wall ports 11 and they are all out oil.

overcome thisdifficulty by providing a I cylinder 1 which theupper portion sufliciently large in its internal diameter to per I mit the entrance of apunch or die-to form the wall ports 11, as clearly shown in Fig. 2. Thepunch freely enters the'enlarged portion 7 at the top of the cylinderh'to the point indicated'bythe line aw-a in Fig; -1, when it begins to extrude the wall of: the cylinderl toiform the wall ports" 1l, as clearly shown I v in Fig. 2.v WVhen this operation is complete,

obviously the enlarged portion of the'cylinder permit the withdrawal of the punch 1 will without difiiculty. e.

means to cause the ports in said bushing to said cylinder adjacent its enlarged end, and

a bushing fitted to'the enlarged end of said cylinder, having ports adapted to register with the extruded wall'ports of said cylinder.

CLARANCE THOMPSON. 

